Improvement in glass jars



WPLLIAM M. KIBC'HNER.

Improvement in Glass-Jars.

1N Patented May 30,1871.

@M eza mwg w PATENT OFFICE.

WIL IAM M. KIRCHNER, 0F PITTSBURG, PENNSYLVANIA.

*lMPROVEMENT IN GLASS JARS.

Specification forming part of Letters Patent No. 115,326, dated May 30, 1871.

To all whom it may concern:

Be it known that I,W1LLIAM M. KIRCHNER, of the city of Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Glass Jars; and I do hereby declare the following to be a full, clear, and exact description thereof, reference being had by letters to the acgasket-seat, also finless, is made atthe base of the screw-thread of the jar, so that I produce a jar made wholly of glass, with the exception of the gasket. The cap referred to forms the subject-matter of a separate application.

In the externally-threaded fruit-jars heretofore made the screw-threadshavecommonly been blown in the two-part mold along with the body of the jar, so that a fin was formed across the gasket-seat and screw threads, which fin prevented the use of a glass cap. To

' getrid of this fin, and. adapt the jar for use with a glass cap, I make what is generally known as a ring-jar, by winding a ring of plastic glass around the neck of the jar, and

then form the screw-thread and finish the jar r by the use of a suitable tool, such as was patented to me by Letters Patent No. 109,825.

. The body of the jar a' is blown in the usual way, after which a ring of plastic glass is formed on the neck. The plug of the tool mentioned above is then inserted into the mouth of the jar. The screw-thread is formed by rotating along with the plug an annular ring, which extends out beyond the plug, so as to leave a space between it and the plug. The plastic ring previously formed around the mouth of the jar is forced up by the jaws of the tool in between the plug and the annular ring,- which latter, having suitable projections on the, inner face, forms a thread, 1), around the mouth; The gasket-seat c is formed against a shoulder in the tool, the jaws of which are so made that when closed they will not come quite flush with the inner face of the annular ring which forms the thread b, so that sufficient space is left between them to form the seat 0 against the shoulder below the annular ring. Thus I make a jar-mouth of this shape without a fin across the gasketseat'and thread, and secureto the jar a perfectly air-tight fastening.

What I claim as my invention, and desire to secure by Letters Patent,-is-

A hand-finished ringjar, having external finless screw-threads and gasket-seat on the neck immediately below the mouth, substantially as described.

In testimony whereof I, the said WILLIAM M. KIRGHNER, have hereunto set my hand.

' WILLIAM M. KIROHNER.

Witnesses W. N. HOWARD, THos. B. KERR. 

